from manim import *



class math1(MovingCameraScene):
    def construct(self):
        self.camera.background_color = BLACK  # 设置背景颜色
        self.camera.frame_width = 100  # 设置边框宽度
        self.camera.frame_height = 60  # 设置边框高度
        self.camera.pixel_height = 1080  # 设置像素高度
        self.camera.pixel_width = 1920  # 设置像素宽度
        self.camera.center = ORIGIN  # 设置中心点位置
        self.camera.scale_factor = 1.0  # 设置缩放因子
        #设置横线
        for i in range(6*2+1):       
            dot1=Dot([-50,5*(i-6),0]).set_opacity(0.5)
            dot2=Dot([50,5*(i-6),0]).set_opacity(0.5)
            if i==6:
                line1=Line(dot1,dot2).set_color(WHITE).set_opacity(0.5)
                
            else:
                line1=Line(dot1,dot2).set_color(WHITE).set_opacity(0.5)
               
            self.add(dot1,dot2,line1)
        #设置竖线
        for i in range(10*2+1):        
            dot3=Dot([(i-10)*5,-30,0]).set_opacity(0.5)
            dot4=Dot([(i-10)*5,30,0]).set_opacity(0.5)
            if i==10:
                line2=Line(dot3,dot4).set_color(WHITE).set_opacity(0.5)
                
            else:
                line2=Line(dot3,dot4).set_color(WHITE).set_opacity(0.5)
            self.add(dot3,dot4,line2)
        #设置三个点
        dot1 = Dot(radius=1, color=RED)  
        dot1.move_to([-47.5,27.5,0]) 
        dot2 = Dot(radius=1, color=YELLOW)  
        dot2.move_to([-42.5,27.5,0])  
        dot3 = Dot(radius=1, color=GREEN)  
        dot3.move_to([-37.5,27.5,0])
        #镜头跟进效果 
        #self.camera.frame.save_state()
        #题目出现
         # 第一个文本对象
        text = Tex(r"$\text{设 } f(x) \text{ 在 } x=a \text{ 的某领域内有定义，在 } x=a \text{ 的某去心领域内可导，}$",
                   tex_template=TexTemplateLibrary.ctex).scale(5).move_to([-10, 0, 0])

        # 第二个文本对象
        text0 = Tex(r"$\text{下述论断正确的是()}$",
                    tex_template=TexTemplateLibrary.ctex).scale(5).next_to(text, RIGHT, buff=1)

        # 第三个文本对象
        text1 = Tex(r"$\text{(A) 若 } \lim\limits_{x \to a} f'(x) = A \text{, 则 } f'(a) = A \text{}$",
                    tex_template=TexTemplateLibrary.ctex).scale(5).move_to([-22, -5, 0])
        text2 = Tex(
                    r"\text{(B)若}$f'\left( a\right) =A$\text{,则}$\lim\limits _{x\rightarrow a}f'\left( x\right) =A$"
                   ,tex_template=TexTemplateLibrary.ctex).scale(5.0).move_to([22,-5,0])
        text3 = Tex(
                   r"\text{(C)若}$\lim\limits _{x\rightarrow a}f'\left( x\right) =\infty $\text{,则}$f'\left( a\right) $\text{不存在}"
                   ,tex_template=TexTemplateLibrary.ctex).scale(5.0).move_to([-22,-12,0])
        text4 = Tex(
                    r"\text{(D)若}$f'\left( a\right) $\text{不存在}\text{,则}$\lim\limits _{x\rightarrow a}f'\left( x\right) =\infty $"
                   ,tex_template=TexTemplateLibrary.ctex).scale(5.0).move_to([22,-12,0])

        self.play(Write(text),Write(text1),Write(text2),Write(text3),Write(text4),Write(text0))
        #镜头拉回
          #分析文本
        #text100=MarkupText("<b><i>分析/解：</i></b>",color=PINK).scale(5.0).move_to([-38,12.5,0])
        #self.play(Restore(self.camera.frame))
       
       
        #题目向上移动
        self.play(text.animate().move_to([-10,20,0]),
                  text1.animate().move_to([-22,15,0]) ,
                  text2.animate().move_to([22,15,0]),
                  text3.animate().move_to([-22,8,0]),
                  text4.animate().move_to([22,8,0]) ,
                  text0.animate().shift(20*UP),
                   FadeIn(dot1),
                    FadeIn(dot2),
                     FadeIn(dot3) )

        #半透明矩阵扩展
        rectangle=Rectangle(color=YELLOW,fill_opacity=0.5,width=1,height=2.8
                            ,stroke_color=YELLOW,stroke_width=0).move_to([-22,15,0])
        rectangle100=Rectangle(color=YELLOW,fill_opacity=0.5,width=1,height=2.8
                            ,stroke_color=YELLOW,stroke_width=0).move_to([-22,8,0])
        self.play(
            rectangle.animate.stretch(45.0,dim=0),
            rectangle100.animate.stretch(45.0,dim=0)
        )
        self.wait(0.1)

        text5 = Tex(
                   r"$f'\left( a\right) =\lim\limits _{x\rightarrow a}\dfrac{f\left( x\right) -f\left( a\right) }{x-a}===\lim\limits _{x\rightarrow a}f'\left( x\right)$"
                   ,tex_template=TexTemplateLibrary.ctex).scale(5.0).move_to([-10,-5,0])
        text6 = Tex(
                   r"\text{洛}",color=GREEN
                   ,tex_template=TexTemplateLibrary.ctex).scale(5.0).move_to([0,-2,0])

        #洛必达三个条件

        text8 = Tex(
                   r"}$1.\dfrac{0}{0}$\text{型}"
                   ,tex_template=TexTemplateLibrary.ctex).scale(5.0).move_to([-22,-15,0])
        text9 = Tex(
                    r"\text{2.去心领域可导} "
                   ,tex_template=TexTemplateLibrary.ctex).scale(5.0).move_to([-22,-20,0])
        text10 = Tex(
                   r"\text{3.洛后极限三种情况：存在,∞,震荡}"
                   ,tex_template=TexTemplateLibrary.ctex).scale(5.0).move_to([-22,-25,0])


        rectangle2=Rectangle(color=BLUE,fill_opacity=0.0,width=45,height=11.5
                            ,stroke_color=BLUE,stroke_width=20)
        rectangle2.move_to([-22, -17, 0])

        text11 = Tex(
                   r"\text{存在性}",color=YELLOW
                   ,tex_template=TexTemplateLibrary.ctex).scale(5.0).move_to([10,-17,0])
        rectangle3=Rectangle(color=BLUE,fill_opacity=0.0,width=45,height=5
                            ,stroke_color=BLUE,stroke_width=20)
        rectangle3.move_to([-22, -25, 0])


        text12 = Tex(
                   r"\text{有用性}",color=YELLOW
                   ,tex_template=TexTemplateLibrary.ctex).scale(5.0).move_to([10,-25,0])
        self.play(Create(text12),Create(text5),Create(text6),Create(text8),Create(text9)
                  ,Create(text10),Create(text11)
                  ,Create(rectangle2),Create(rectangle3))
        
        #半透明矩阵扩展
        rectangle101=Rectangle(color=GREEN,fill_opacity=0.5,width=1,height=2.8
                            ,stroke_color=YELLOW,stroke_width=0).move_to([22,15,0])
        rectangle200=Rectangle(color=GREEN,fill_opacity=0.5,width=1,height=2.8
                            ,stroke_color=YELLOW,stroke_width=0).move_to([22,8,0])
        self.play(
            rectangle101.animate.stretch(45.0,dim=0),
            rectangle200.animate.stretch(45.0,dim=0)
        )
        

        





        self.wait(1)